A basal diet (0.8 g/kg dNa) was formulated in which each of the two sources (NaHCO3 and Na2SO4) were supplemented in such a way to attain four levels (1.7, 2.6, 3.5, and 4.4 g/kg) of total dNa, respectively, under 4×2 factorial arrangement. Eight dietary treatments were replicated four times, with 40 birds in each replicate (n = 1,280). The diets supplemented with Na2SO4 to attain higher levels of dNa showed highest BW gain and feed intake (FI) during d 1 to 10 (interaction effects) while 2.6 g/kg dNa exhibited improved BW gain and gain:feed (FG) during d 11 to 20. Linear rise in daily water intake (DWI) was associated with diets containing increasing dNa during d 1 to 42 (p≤0.036). During the first 10 d, DWI:FI was found highest in NaHCO3 diets while Na2SO4 diets showed highest DWI:FI during last 10 d of the experiment (p≤0.036). Increasing dNa and changing Na2SO4 with NaHCO3 salt increased pH and resulted in poor growth performance. Dressing weight (p≤0.001) and abdominal fat (p≤0.001; quadratic effect) were reduced, whereas breast (p≤0.001) and thigh (p<0.001) weights were aggravated with increasing dNa (linear effects). Present findings suggested higher levels of dNa from Na2SO4 as the supplemental salt in broiler diets would produce better growth performance, especially in first ten days of life, and improve carcass and body organ characteristics.
Keywords: Broiler; Growth and Carcass Responses; Phase Feeding Program; Serum Mineral Chemistry; Sodium.